Expandable interbody implant with lordosis correction

Abstract

A spinal implant for placement between vertebral bodies includes a first member for engaging one of the vertebral bodies, a second member for engaging an opposing one of the vertebral bodies, and at least one extendable support element for inducing movement of the entire first member away from the second member. The first member is connected to the second member such that the first member moves away from the second member by a larger distance at a first end of the implant than at a second end of the implant. A connecting member may connect the first and second members together at the second end of the implant. The connecting member may include one or more rotatable linkages, or the connecting member may be an extension of one of the first and second members slidably received within a track defined within the other of the first and second members.

The invention claimed is: 
     
       1. A method of performing interbody fusion, the method comprising:
 positioning a spinal implant between a first vertebral body and a second vertebral body, wherein the spinal implant includes a top plate including a first surface to engage the first vertebral body, a housing including a second surface to engage the second vertebral body, and a hydraulic system between the top plate and the housing; and 
 inducing, based on an actuation force to the hydraulic system, movement of the top plate away from the housing at both a first end portion and a second end portion of the spinal implant, wherein 
 the induced movement of the top plate away from the housing is guided by a linkage, such that the top plate moves away from the housing by a first distance at the first end portion of the implant and a second distance at the second end portion of the implant, and 
 the first distance is greater than the second distance. 
 
     
     
       2. The method of  claim 1 , wherein the linkage is positioned at the second end portion of the implant such that the induced movement guides the top plate away from the housing by constraining movement of the top plate at the second end portion of the implant. 
     
     
       3. The method of  claim 1 , wherein the hydraulic system is located at the first end portion of the spinal implant. 
     
     
       4. The method of  claim 1 , wherein the actuation force includes delivering a pressurized fluid to the hydraulic system. 
     
     
       5. The method of  claim 1 , further comprising inducing, based on the actuation force, movement of the linkage. 
     
     
       6. The method of  claim 1 , wherein the linkage is a rotatable linkage including a first end and a second end, the first end of the linkage being pivotably connected to the top plate and the second end of the linkage being pivotably connected to the housing. 
     
     
       7. The method of  claim 6 , wherein the induced movement of the top plate away from the housing is guided by the rotatable linkage. 
     
     
       8. The method of  claim 1 , wherein the induced movement is constrained by a stop member extending between the top plate and the housing. 
     
     
       9. The method of  claim 1 , further comprising locking a position of the top plate with respect to the housing. 
     
     
       10. The method of  claim 9 , wherein the locking is provided by a locking system that includes a lower lock support positioned within the housing and a corresponding upper lock support connected to an underside of the top plate. 
     
     
       11. The method of  claim 10 , wherein the upper lock is integrally formed with the hydraulic system. 
     
     
       12. The method of  claim 9 , further comprising unlocking the position of the top plate with respect to the housing. 
     
     
       13. The method of  claim 1 , wherein the induced movement is provided by sliding a piston away from a bottom of a cylinder in the housing. 
     
     
       14. The method of  claim 1 , wherein the induced movement is provided via a delivery tool. 
     
     
       15. The method of  claim 1 , wherein the hydraulic system is angled toward the first end portion of the implant.